N.J. weather: State faces ‘enhanced risk’ of isolated tornadoes, strong thunderstorms from Ida’s remnants


While many forecasters were originally concerned about torrential rain from Tropical Storm Ida’s remnants causing widespread flooding Wednesday and Thursday, concerns are now growing over the possibility of isolated tornadoes popping up in some parts of New Jersey.

The national Storm Prediction Center has issued new forecast maps that now place a large section of Central New Jersey under a “slight” risk of getting severe weather and most of South Jersey under an “enhanced” risk.

The enhanced risk includes the possibility of isolated tornadoes touching down on Wednesday and Wednesday night.

“The tornado threat has definitely increased over the past few days, especially in coastal-southern New Jersey and Delmarva,” said Nick Carr, a meteorologist at the National Weather Service’s regional forecast office in Mount Holly, which covers most of New Jersey, eastern Pennsylvania, eastern Maryland and all of Delaware.

“Since a few days ago, the system is looking a little more amplified, meaning the resulting low (from now-Tropical Depression Ida) will probably start strengthening again,” Carr said. “The actual low itself will probably get stronger and the wind fields around it will get a bit stronger.”

Carr said warmer air is expected to push in from the far south, creating more instability in the atmosphere. That could set the stage for strong thunderstorms and possible isolated tornadoes, with the threat being highest in areas south of Ida’s main track, he said.

The remnants of Tropical Storm Ida are expected to hit New Jersey starting Wednesday afternoon with drenching rain, flash flooding and the risk in South Jersey of severe thunderstorms and isolated tornadoes.

If that forecast remains unchanged on Wednesday, when the stormy weather is expected to arrive, this would put the New Jersey counties of Cape May, Cumberland, Atlantic, Salem, Gloucester, Camden and southern Burlington in the highest threat zone. Carr said he can’t rule out an isolated tornado in coastal Ocean County as well.

For most of the northern half of New Jersey, Carr said, the main threat from Ida’s remnants is heavy rain — which could cause flash flooding in areas near rivers, streams and other waterways, along with rapid flooding on streets with bad drainage.

A flash flood watch, which is not as urgent as a flash flood warning, is in effect in all of the state’s 21 counties from early Wednesday through 2 p.m. Thursday.

Current weather radar

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Len Melisurgo may be reached at LMelisurgo@njadvancemedia.com.